MANN ON A MISSION: Peyton Manning and the Broncos host the Ravens tomorrow in Denver.

What makes this weekend great, could spoil next Sunday.

Last year the Giants shocked the football world by knocking off the 15-1 Packers on their way to a Super Bowl championship. This season the double-digit underdogs reside in the AFC, and the Texans and Ravens are trying to ruin everyone’s — everyone outside of Houston and Baltimore, that is — dream of a Tom Brady-Peyton Manning AFC Championship Game.

“New England and Denver are clearly the favorites and for a reason. But, my gosh, we see so many upsets in the playoffs, it’s endless,” said CBS analyst Phil Simms, who will be calling the Patriots-Texans game on Sunday.

Green Bay beat the Giants last year late in the regular season, but that did not compare to the beat downs dished out by the Broncos (34-17 in Week 15) and Patriots (42-14 in Week 14) to their respective opponents this weekend. But there is a danger of that playing against the AFC’s top seeds, though.

“No matter what New England and Denver says to themselves they beat those teams earlier in the year, and it wasn’t that long ago and they beat them soundly,” Simms said. “You can’t wipe that from the memory bank. … But you have to get to the point where there’s zero complacency. And that’s the challenge for Denver and New England. …. They are two teams that understand these things, and they probably have a good chance as any team in the NFL at making sure that situation doesn’t happen to them.”

Simms admits it is hard to resist the lure that would come with Brady and Manning meeting once again for a spot in the Super Bowl. This one would come in Mile High, after Manning and the Colts parted ways this offseason. Manning had to sit out last season after several career-threatening neck surgeries and Indianapolis was on the verge of selecting Andrew Luck with the No. 1 pick.

“I’m a fan first, there’s no doubt about it,” the former Giants quarterback said. “I was glad to be there with Ray Lewis for his last game in Baltimore as a broadcaster and a fan. I’ve done the Peyton-Brady matchups before and if we do get that, yeah, it’s going to be huge. I know the focus is going to be incredible and it’d be good to be part of that.”

But first the Broncos must get by Lewis and the Ravens, and the Patriots have to beat the Texans in their first postseason game since losing to the Giants in Super Bowl XLVI. When asked about the Giants’ late-season struggles this season, Simms pointed to the grind of coming back after reaching a Super Bowl forces your season into February. That, in Simms’ mind, makes the Patriots’ run all the more noteworthy.

“It’s such a culture up there that it just doesn’t change. The coach and the quarterback are so strong mentally, and personality-wise I would say that the biggest reason they don’t have down years,” Simms said of Brady and Bill Belichick.

“They get it done. It’s the toughest combination in history. Tom Brady is never satisfied, and we see Bill Belichick, too. He never gets tired of what’s going on.’’